Transmission of information is a common practice in modern data processing systems, particularly in telematic networks connecting a great number of computers, such as the INTERNET. Security is of the utmost importance in this context; in fact, any computer connected to the INTERNET is prone to be accessed by any other user of the network.
Several techniques have been proposed in the last years for ensuring that information stored in a computer cannot be compromised. For example, anti-viruses inspect programs in order to prevent running of harmful code that could impair operation of the computer. On the other hand, firewalls are designed to prevent unauthorised access to computers of a private network; particularly, all messages entering the private network pass through the firewall, which examines each message and blocks those that do not meet specified security criteria.
Filtering is also used for controlling access to the INTERNET, by analysing incoming and outgoing packets and letting them pass or halting them based on the address of a source or destination, respectively. For example, a bozo list or kill file enables the computer to block all messages from a specified individual; moreover, it is also possible to prevent access to specific web sites from the computer.
However, this scenario is not completely satisfactory. In particular, the inventor has discovered that none of the solutions known in the art is effective in protecting privacy of a user of the computer. As a consequence, the user of the computer is very often spammed with junk e-mail or newsgroup postings, generally consisting of unsolicited advertising for some product. Moreover, the user of the computer may also receive searing messages (generally known as flames) in which a writer attacks him or her in overly harsh, and often personal, terms.
It is an object of the present invention to overcome the above-mentioned drawbacks. In order to achieve this object, a method as set out in the first claim is proposed.